Functionality to check current indentation status

[Deniz Dogan]

Is there any generic functionality for checking whether a specific
line is indented appropriately according to major-mode? I mean other
than indenting it and seeing whether anything was modified.

If not, it would be useful for e.g. a minor-mode which would highlight
lines that are not correctly indented, or for binding TAB to some
imaginary function indent-or-expand-abbrev, which would indent the
line if not already correct, otherwise call `expand-abbrev'.

-- 
Deniz Dogan